Instead of moving the file out and starting with a fresh one each time, I've been simply copying the SV file out, and letting Windows rename it (1), (2), etc, as I go. So my file is cumulative larger over the period. Assuming I upload them in the correct chronological order, that will still work fine, right?

That works fine.. Name is irrellevant, a long as you upload in the correct order.

Also, wether you use a new or "incremental" file is also of no consequence. Saving old data, is only usefull for yourself, when you open the addon inside the game._________________Doing census on various servers

Where it says "Version", change 6.0.0 to 5.0.2 and save. The submiter will then accept the file and if you open up censusplus in the game it'll say version 5.0.2, after the Warcraft Realms site is updated you'll have to do this again and change the version back to 6.0.0